1. Field of the Invention
The present invention relates to a display apparatus having a function for detecting touch or proximity of a finger, a pen or the like with or to a detection face by the user, that is, a function of touch detection such as a touch panel or a like apparatus. The present invention further relates to a touch detection apparatus having the touch detection function.
2. Description of the Related Art
For a touch detection method for a touch panel, three types including an optical type, a resistance film type and a capacitance type are known.
Meanwhile, in order to associate electrical variation occurring in response to touch or proximity with position information, a great number of wiring lines combined so as to be capable of achieving position specification and arranged in a matrix are required. According to a method of position detection which depends upon a combination of wiring lines, a great number of wiring lines are required to increase the resolution of the detection.
Therefore, in the three detection methods, a driving method for detecting a touch position or a proximity position while a line from which an electric variation is to be outputted is scanned in one direction is becoming the mainstream. For example, a driving method of the optical type is disclosed in Hirotaka Hayashi etc. “Optical Sensor Embedded Input Display Usable under High-Ambient-Light Conditions,” SID 07 DIGEST, p. 1105 (hereinafter referred to as Non-Patent Document 1). Meanwhile, a driving method of the resistance film type is disclosed in Bong Hyun You etc., “12.1-inch a-Si:H TFT LCD with Embedded Touch Screen Panel,” SID 08 DIGEST p. 830 (hereinafter referred to as Non-Patent Document 2). Further, a driving method of the capacitance type is disclosed in Joohyung Lee etc., “Hybrid Touch Screen Panel Integrated in TFT-LCD,” SID 08 DIGEST p. 834 (hereinafter referred to as Non-Patent Document 3). Here, the term “line” signifies an array in an X direction or a Y direction of fine sensor sections arranged two-dimensionally in accordance with a predetermined rule for touch detection.
Incidentally, if a touch panel is provided in an overlapping relationship on a display panel, then the thickness of the overall displaying module increases. Further, a retaining member for retaining the touch panel on the display panel is required, and the area of a frame (portion around an effective detection face) increases and the cost increases.
Therefore, in recent years, the mainstream of the type to be developed has changed from a type wherein a touch panel is mounted in an overlapping relationship on a display panel to another type wherein a touch panel is built in a display panel (refer to Non-Patent Documents 1 to 3 and Japanese Patent Laid-Open No. 2008-9750 (hereinafter referred to as Patent Document 1)).
In the following description, “display apparatus with touch sensor” is used as a denomination of an apparatus which has any form of incorporation of a touch panel in regard to whether the touch panel is mounted in an overlapping relationship on a display panel or is formed integrally with a display panel.